On Thu, 12 Feb 2004 06:29:51 +1000, Mike Borgelt
wrote:

I figure that the choice with a personal chute is small but with a
whole ship chute it is zero.

I once saw a movie of the BRS drop test on a C150 simulating its
arrival under a deployed BRS chute. I doubt that the Cessna was
useable again even though it was a symmetrical level attitude when it
hit with no drift. I'd hate to hit at a similar descent rate in a
glider. In Oz we've had a few people do hard landings in the last
couple of years. Some are considered lucky to be walking but the
gliders are repairable. Air bags may be essential.

I know an FK-9 ultralight that has already survived three (!)
parachute landings (and is still flying - here's the photo:
http://www.fk-lightplanes.com/FK-History/9Mk3_3_57.jpg), and I read
about one SR-20 or 22 that is also flying again after a chute landing.

The problem of a glider that my butt is two inches from the ground in
a worst-case impact at 20 ft/sec (but the BRS systems for gliders are
designed in order to get an impact at 45 degrees nose down attitude,
maximizing the energy absorption of the fuselage nose).

Not to mention the possible extremely high (220 kts) speed of a
glider with a missing tail or wing. The deployment speed of the BRS of
the Cirrus is limited to a pretty low speed (iirc 150 kts IAS).

In Germany BRS systems are mandatory for ultralight aircraft (some of
these little planes reach cruise speeds in excess of 140 kts (limited
by the maximum deployment speed of the BRS) at a weight of about 1.000
pounds. Each year there are a couple of successful BRS savings.


Bye
Andreas